Hormones and bile acids as biomarkers for the characterization of animal management in prehistoric sheepfold caves: El Mirador case (Sierra de Atapuerca, Burgos, Spain)

Abstract

Early husbandry practices that include herd management and the use of livestock areas such as sheepfold caves can be analysed in the context of different disciplines (e.g. zooarchaeology, micromorphology, and archaeobotany). In this study, a new and standard method for the determination of bile acids and steroidal hormones that incorporates microwave extraction-liquid chromatography-mass spectrometry was used. This method has been applied successfully to analyse Neolithic fumier deposit facies from the El Mirador cave, a location that was used as a prehistoric sheepfold and is located in the Atapuerca range (Burgos, Spain). The results obtained demonstrated that the analysis of bile acids can be useful for the identification of remains of ruminant residues in the facies studied. In addition, the progesterone/deoxycholic acid ratio has been used as a possible biomarker to improve our understanding of flock management, including the separation of pregnant and nursing ewes from the rest of the herd to avoid the rejection of the lamb and keep them safe and healthy.